Atomistic Insights on Prebiotic Phosphorylation of Methanol from Schreibersite (Fe2NiP) Corrosion: Ab Initio Computational Study

The prebiotic history of phosphorus is a matter of debate in the scientific community: its origin, how it landed on Earth, the selective speciation of the phosphate, and its inclusion in the organic matrix are the main unsolved issues. In this regard, Schreibersite ((Fe,Ni)₃P), a mineral present in iron meteorites, can play a fundamental role as a carrier of reactive P which, as a result of the weathering processes, produces oxygenated phosphorus compounds, even the phosphate among others. In the present paper, we studied the interaction of methanol (alone and mixed with water) with the Schreibersite surfaces throughout periodic density functional theory calculations at the PBE level. The results indicate that Schreibersite promotes the deprotonation of methanol and water both from thermodynamic and kinetic points of view, thus enabling the first step toward corrosion. We have simulated advanced stages of the corrosion process up to the formation of the phosphate and the phosphorylated form of methanol (methyl phosphate), showing that the formation of both products is thermodynamically favored, as well as its solubilization, which allows other water molecules to proceed with further corrosion of Schreibersite.